Sevana AQuA: Promising Audio Quality Assessment for AMR-WB, EVS-WB, and EVS-SWB Codecs


In the ever-evolving landscape of telecommunication technologies, efficient audio compression codecs play a pivotal role in delivering high-quality voice communication over limited bandwidth. The quality of audio codecs is traditionally assessed through Mean Opinion Score (MOS) testing, which involves subjective human evaluations. However, the need for automated, reliable, and consistent methods for evaluating codec quality led to the development of Sevana AQuA (Audio Quality Assessment) – a groundbreaking solution capable of differentiating quality based on MOS scores among various codecs, including Adaptive Multi-Rate Wideband (AMR-WB), Enhanced Voice Services Wideband (EVS-WB), and Enhanced Voice Services Super-Wideband (EVS-SWB).

The Significance of Codec Quality Assessment

As telecommunication providers strive to deliver crystal-clear voice quality over diverse networks, codec development has become a critical aspect of ensuring optimal user experience. The efficient utilization of bandwidth, reduction of latency, and preservation of voice naturalness are among the key parameters codec developers aim to enhance. Traditional subjective testing involves a panel of human listeners providing subjective quality scores, often measured by MOS. However, this process can be time-consuming, expensive, and potentially inconsistent due to variations in human perception.

Enter Sevana AQuA

Sevana AQuA represents a paradigm shift in codec quality assessment by leveraging advanced algorithms to automatically evaluate audio quality. The software analyzes audio samples encoded using different codecs, such as AMR-WB, EVS-WB, and EVS-SWB, and assigns them MOS scores based on a robust computational model. This model emulates human auditory perception, enabling AQuA to provide objective and repeatable quality assessments.

Key Features and Functionalities

  1. Objective Quality Scoring: Sevana AQuA employs advanced signal processing techniques and perceptual models to generate objective quality scores for each codec. These scores are highly correlated with human-perceived quality, making them an accurate representation of user experience.
  2. Codecs Comparison: The software enables direct comparisons of codec performance. Telecommunication companies and developers can assess how different codecs perform under varying network conditions, aiding them in selecting the most suitable codec for their requirements.
  3. Scalability and Efficiency: Sevana AQuA’s automated assessment eliminates the need for extensive human listener panels, reducing time and costs associated with quality testing.
  4. Wide Applicability: The software is versatile, accommodating different codecs and network conditions. It can be integrated into the codec development pipeline or used to assess codec performance in real-world scenarios.
  5. Continuous Improvement: Sevana AQuA can be fine-tuned and updated as new codecs are introduced or existing ones are optimized. This ensures that the evaluation remains up-to-date with technological advancements.


Sevana AQuA represents a pivotal advancement in the field of audio codec quality assessment. By offering automated, objective, and reliable MOS scoring for codecs such as AMR-WB, EVS-WB, and EVS-SWB, the software empowers telecommunication companies, developers, and researchers to make informed decisions about codec selection and optimization. As the demand for high-quality voice communication continues to grow, Sevana AQuA plays a crucial role in enhancing user experience across various networks and devices.

End-to-end audio quality testing: is there a simple but powerful tool for end-to-end audio quality testing and file comparison?

Meet Sevana AQuA – Audio Quality Analyzer 🔉
It is a simple but powerful tool to provide perceptual voice quality testing and audio file quality comparison.
The human ear is a non-linear system, which produces an effect named masking. Masking occurs on hearing a message against a noisy background or masking sounds.
AQuA perceptual model is based on research of four different scientists who discovered influence of different frequency bands (the so-called critical bands) to human perception.
The value of spectrum energy in frequency bands can be used for different purposes; one of which is the sound signal quality estimation.
However, using only critical bands discovered by one scientist does not allow getting an estimation objective enough, since they show only one of the aspects of perception or speech production.
AQuA can determine energy in various critical bands as well as in logarithmic and resonator bands, that allows taking into account more properties of hearing and speech processing.
We know three tools of this kind available on the market: POLQA, ViSQOL, AQuA. Please contact us if you know other tools or like to evaluate Sevana AQuA.


What are Sevana call quality testing offerings?
We are happy to offer all kinds of tools to test call quality in any network: VoIP, GSM, 5G, satellite
🔹 Vast call quality monitoring both on audio and protocol levels
🔹 Passive real-time and active scheduled call quality analysis
🔹 Call quality problem root cause analysis
🔹 Reliable network and payload MOS
🔹 Mobile-to-mobile call quality tests

contact center end-to-end voice quality testing
Contact Center end-to-end voice quality testing value clients and agents

Forecasting voice quality using network statistics was sufficient for the days when one could control the network.

Different suppliers, networks, systems, software, hardware influence customer and agent experience. Only network metrics cannot ensure that all entities involved in the voice path work properly and give the best or satisfactory quality of caller experience (QoE).

Using network parameters to calculate MOS for cloud-based contact center and agent connection does not represent possible issues inside the cloud or voice paths connected to it.

Automation of test calls simulating caller and agent activity that will play audio file of “excellent” quality (the so-called reference audio) over the environment and record actual audio received by correspondent endpoints will give objective quality score for the whole voice path if one can compare the reference and test files for quality loss.

Sevana AQuA makes this comparison fast and easy providing reliable MOS score and reports on various quality issues that affected the caller perception. Furthermore, AQuA will pinpoint timestamps of the conversation where the problems occurred and indicate the type of impairment, which will help to identify the “faulty” part of the voice path.

This approach is useful at any stage of deployment – evaluation, piloting, transition, or production. If on demand, or scheduled voice quality scoring is not enough one can use Sevana PVQA for real-time voice quality analysis, problems alerting and reporting within the same feature of indicating impairments that affected the quality loss, but in real time.

Waveform analysis is the approach that gives objective overview on voice quality in cloud contact centers. Sevana tools perform perfectly well for voice quality measurement and analysis in the cloud.

Sevana AQuA is the most flexible too for end-to-end voice quality testing:
🖋 Testing across multiple devices and networks
Improve your system’s QoE and invest in the future – waveform analysis works seamlessly for VoLTE, VoWiFi, RCS or any other approach
🖋 Flexible integration considering every client’s requirement
Feel free to develop your own call quality monitoring solutions implemented by your own staff
🖋 Easy integration into any kind of hardware
Work on any hardware of your choice
🖋 Automated and fast testing cycle reducing operating costs
Save time and money using automated quality monitoring system
🖋 Streamline root cause analysis
Automate call quality assessment and ease problem root cause identification
🖋 Customer-oriented support
We are always happy to help save our customer’s time
Keep an eye on call quality with

IVR prompt verification and IVR prompt test automation are quite common tasks, however, there is probably no particular tool to make it really easy. And this is because you might have not heard about Sevana AQuA.
General purpose of AQuA is to analyze quality of the test audio by comparing it with the reference of original quality. However, unlike other similar tools one can use AQuA for IVR prompt verification, because comparing different audio files will naturally result in low quality score. Using AQuA for IVR prompt verification you verify the prompt and test connection quality within the same test call.

Contact us to learn more on using AQuA for IVR prompt verification.

Do you want to compare reference and test audio to evaluate the quality in your own language, but don’t have a tool?
AQuA is an audio quality analyzer that gives you even more flexibility:
✔️Language Independence – AQuA can evaluate quality of audio in any language.
✔️Long and short calls support – analyzes audio shorter than 4 seconds and longer than 30 seconds.
✔️Works with Stereo Audio – test signals may be mono or stereo, narrow, wideband and super wideband.
✔️Allows parameters profiling – configurable perceptual model that best suits your test environment.

#Great #News

We are happy to announce availability of AQuA 8.x that includes both AQuA and PVQA technology, providing additional information on #impairments in the #test audio that #affect human perception.
We encourage to try this version out by requesting an update for existing customers and trial version for new prospects.

Contact us.